Protective clothing is necessary in handling and cleaning up hazardous chemicals. One type of material commonly used in such protective clothing comprises a chemical barrier, such as polytetrafluoroethylene (PTFE) film, carried on both sides of a fabric substrate. In handling chemicals or cleaning up spills, a person typically encounters a variety of tools and other objects with sharp or protruding edges, and protective clothing must be capable of withstanding considerable wear and tear and fairly rough use. Unfortunately, many chemical barriers can be punctured under such conditions. Moreover, many chemical barriers are inherently inflexible, and may split during fabrication or wear of protective clothing.
If the exterior chemical barrier film is punctured, the fabric substrate of such composite material may be capable of preventing the puncture of the interior barrier film, and thus, of preserving the structural integrity of the barrier and the protective clothing as a whole. Although chemicals may not be able to pass through the material as a whole, however, if the outer chemical barrier is split or punctured, chemicals can penetrate into the fabric substrate and many will tend to wick through the fabric substrate and contaminate areas removed from the point of penetration. When the garment is repaired, large portions of the composite material must be replaced, thereby increasing repair costs and unnecessarily compromising the structural integrity of the garment.
Compositions for preventing the wicking of liquids through a fabric, per se, are known, and they are based on a variety of chemical compounds. Many conventional antiwicking agents, however, are not universal in their action. For example, silicone based antiwicking agents resist wicking of aqueous solutions, but not of organic solvents. Oter antiwicking agents suffer the additional defect of having to be applied in amounts that create unacceptable stiffness in the fabric.
The subject invention, therefore, is directed to novel antiwicking compositions which impart to a fabric more universal resistance to wicking and do not appreciably decrease the flexibility of the fabric.
The subject invention is further directed to methods for imparting to a fabric more universal resistance to wicking whereby the flexibility of the fabric is not appreciably decreased.
It also is directed to flexible fabrics which are more universally resistant to wicking.